The construction of caisson breakwaters dates from ancient times (Brindisi battle and Caesarea Maritima, Roman Empire) of yore but has evolved with regards to technology and the materials available at all times (wood, gravel, and rubble mound). The growth in draught in vessels searching for deep water depths for berthing plus environmental problems have led to the 20th century facilitating the boom in vertical types and concrete caissons built in different ways (dry and floating techniques). Furthermore, structural criteria gave way to functional, environmental, and aesthetic criteria. The search for new, more efficient forms led to the construction of increasingly more complex elements including many that still require an economically viable construction system. To where will this search for new materials and forms take us? The use of composite materials could be considered, at the moment, as too expensive, but analyzing the cost with a wider approach, as Life Cycle Assessment, shows us that caissons in composite materials are cost effective and could be a solution. Furthermore, the possibility of using recyclable composites opens up big opportunities of using these materials at affordable costs. Caissons in composites or recycled composites are then a real alternative to concrete caissons. In Spain, two examples can be observed: a berthing area in Canary Island (Puerto del Rosario, South Atlantic Ocean) and a crown wall in Cartagena using polyester fiber bars (Mediterranean Sea). European policy in matters of sustainability promotes the circular economy, which means not only consider construction of caissons in recycled composites should be considered but also the comparison of all materials and construction procedures. Lastly, the calculation of the Environmental Product Declaration (EPD) should be promoted.

Martín-Antón, M.; del Campo, J.M.; Negro, V.; Luengo Frades, J.; Moreno Blasco, L.J., and Jiménez Verdejo, J.R., 2020. Land use and port-city integration in reclamation areas: A comparison between Spain and Japan. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 278–282. Coconut Creek (Florida), ISSN 0749-0208.Land reclamation is an increasingly widespread practice, especially in Asia in recent years as a means to provide land above sea level in cities with land shortage. This is the case of Japan, especially in the populated bays of the south coast (Tokyo, Nagoya, Osaka-Kobe). After a worldwide research on this subject (Martín-Antón et al., 2016), a more specific study of the reclaimed areas in Spain and Japan, with their respective land uses, is made in this work to show the needs of growth of the port cities of each country. Two representative bays have been analyzed in detail, namely Algeciras-Gibraltar Bay in Spain and Osaka-Kobe Bay in Japan. The Algeciras Bay has a total reclaimed area of 5.6 km2 whereas Osaka Bay has almost 160 km2 built over the centuries. In the latter, a large percentage of the new land is currently dedicated to residential use (17%), about 28 km2. Much of the housing land is next to, or even surrounded by, industrial zones, which add up to more than 60 km2 (almost 40%), compared to 24% in Algeciras. In Gibraltar (Algeciras Bay), the reclaimed area with residential use is 0.5 km2. It is remarkable the land areas in disuse: 8% of the total in Osaka Bay and 22% in Algeciras Bay. However, more and more land reclamation works are being built, including unfilled water areas surrounded by breakwaters (some of them to be filled with solid waste), such as the 2.6 km2 in Osaka Bay. Another use is energy production, with 0.6% of the total reclaimed area in Osaka Bay dedicated to solar power plants (0.89 km2). This article aims to make a reflection on current urban needs in port areas, port-city integration and the impact on the landscape of large maritime works.

Estimation of wave run-up has been of increasing concern for offshore wind structures and a critical aspect for designers. The highly nonlinear phenomenon makes the study difficult. That is the reason for the very few design rules and experimental data available to estimate it. Actual wave run-up is greater than commonly predicted. The goal of this research is to benchmark the theoretical formulations with the results of the physical model tests performed by Deltares in the field of crest elevation, run-up, forces and pressures. The laboratory reproduced in a wave tank (75 m length; 8.7 m width; 1 m depth; and a 1:60 scale, with Froude similarity) an offshore power converter platform located at intermediate water depths (25–43.80 m) in the Southern North Sea, designed by the Norwegian company Aibel. The purpose of this research is to offer a preliminary design guide for wave run–up using theoretical expressions both for cylinders and gravity based structures (GBS), leaning on the cited laboratory tests to validate the results obtained by such theoretical models.